1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
This Readme file describes the floppy driver.
FAQ list:
=========
A FAQ list may be found in the fdutils package (see below), and also
at http://www.club.innet.lu/~year3160/floppy/FAQ.html
Lilo config options (Thinkpad users, read this)
===============================================
The floppy driver is configured using the 'floppy=' option in
lilo. This option can be typed at the boot prompt, or entered in the
lilo configuration file.
Example: If your kernel is called linux-pre2.0.9, type the following line
at the lilo boot prompt (if you have a thinkpad):
linux-pre2.0.9 floppy=thinkpad
You may also enter the following line in /etc/lilo.conf, in the description
of linux-pre2.0.9:
append = "floppy=thinkpad"
Several floppy related options may be given, example:
linux-pre2.0.9 floppy=daring floppy=two_fdc
append = "floppy=daring floppy=two_fdc"
If you give options both in the lilo config file and on the boot
prompt, the option strings of both places are concatenated, the boot
prompt options coming last. That's why there are also options to
restore the default behavior.
If you use the floppy driver as a module, use the following syntax:
insmod floppy 'floppy="<options>"'
Example:
insmod floppy 'floppy="daring two_fdc"'
Note that in this case 'floppy=' should only be typed out once, and
not once for each option. You need at least modules-1.3.57 for this
method. However, the older environment variable based syntax is still
available:
(sh syntax): floppy="daring two_fdc" insmod floppy
(csh syntax): setenv floppy "daring two_fdc" ; insmod floppy
Some versions of insmod are buggy in one way or another. If you have
any problems (options not being passed correctly, segfaults during
insmod), first check whether there is a more recent version. If there
isn't, use the old method using environment variables.
The floppy related options include:
floppy=asus_pci
Sets the bit mask to allow only units 0 and 1. Obsolete, as
this is the default setting anyways
floppy=daring
Tells the floppy driver that you have a well behaved floppy controller.
This allows more efficient and smoother operation, but may fail on
certain controllers. This may speed up certain operations.
floppy=0,daring
Tells the floppy driver that your floppy controller should be used
with caution.
floppy=one_fdc
Tells the floppy driver that you have only floppy controller (default)
floppy=two_fdc
floppy=<address>,two_fdc
Tells the floppy driver that you have two floppy controllers. The
second floppy controller is assumed to be at <address>. This
option is not needed if the second controller is at address
0x370, and if you use the 'cmos' option
floppy=thinkpad
Tells the floppy driver that you have a Thinkpad. Thinkpads use an
inverted convention for the disk change line.
floppy=0,thinkpad
Tells the floppy driver that you don't have a Thinkpad.
floppy=omnibook
floppy=nodma
Tells the floppy driver not to use Dma for data transfers.
This is needed on HP Omnibooks, which don't have a workable
DMA channel for the floppy driver. This option is also useful
if you frequently get "Unable to allocate DMA memory" messages.
Indeed, dma memory needs to be continuous in physical, and is
thus harder to find, whereas non-dma buffers may be allocated
in virtual memory. However, I advise against this if you have
an FDC without a FIFO (8272A or 82072). 82072A and later are
OK. You also need at least a 486 to use nodma.
If you use nodma mode, I suggest you also set the FIFO
threshold to 10 or lower, in order to limit the number of data
transfer interrupts.
floppy=dma
Tells the floppy driver that a workable DMA channel is available
(the default).
floppy=nofifo
Disables the FIFO entirely. This is needed if you get "Bus
master arbitration error" messages from your ethernet card (or
from other devices) while accessing the floppy.
floppy=fifo
Enables the FIFO (default)
floppy=<threshold>,fifo_depth
Sets the FIFO threshold. This is mostly relevant in DMA
mode. If this is higher, the floppy driver tolerates more
interrupt latency, but it triggers more interrupts (i.e. it
imposes more load on the rest of the system). If this is
lower, the interrupt latency should be lower too (faster
processor). The benefit of a lower threshold is less
interrupts.
To tune the fifo threshold, switch on over/underrun messages
using 'floppycontrol --messages'. Then access a floppy
disk. If you get a huge amount of "Over/Underrun - retrying"
messages, then the fifo threshold is too low. Try with a
higher value, until you only get an occasional Over/Underrun.
It is a good idea to compile the floppy driver as a module
when doing this tuning. Indeed, it allows to try different
fifo values without rebooting the machine for each test. Note
that you need to do 'floppycontrol --messages' every time you
re-insert the module.
Usually, tuning the fifo threshold should not be needed, as
the default (0xa) is reasonable.
floppy=<drive>,<type>,cmos
Sets the CMOS type of <drive> to <type>. This is mandatory if
you have more than two floppy drives (only two can be
described in the physical CMOS), or if your BIOS uses
non-standard CMOS types. The CMOS types are:
0 - Use the value of the physical CMOS
1 - 5 1/4 DD
2 - 5 1/4 HD
3 - 3 1/2 DD
4 - 3 1/2 HD
5 - 3 1/2 ED
6 - 3 1/2 ED
16 - unknown or not installed
(Note: there are two valid types for ED drives. This is because 5 was
initially chosen to represent floppy *tapes*, and 6 for ED drives.
AMI ignored this, and used 5 for ED drives. That's why the floppy
driver handles both)
floppy=unexpected_interrupts
Print a warning message when an unexpected interrupt is received
(default behavior)
floppy=no_unexpected_interrupts
floppy=L40SX
Don't print a message when an unexpected interrupt is received. This
is needed on IBM L40SX laptops in certain video modes. (There seems
to be an interaction between video and floppy. The unexpected interrupts
only affect performance, and can safely be ignored.)
floppy=broken_dcl
Don't use the disk change line, but assume that the disk was
changed whenever the device node is reopened. Needed on some
boxes where the disk change line is broken or unsupported.
This should be regarded as a stopgap measure, indeed it makes
floppy operation less efficient due to unneeded cache
flushings, and slightly more unreliable. Please verify your
cable, connection and jumper settings if you have any DCL
problems. However, some older drives, and also some Laptops
are known not to have a DCL.
floppy=debug
Print debugging messages
floppy=messages
Print informational messages for some operations (disk change
notifications, warnings about over and underruns, and about
autodetection)
floppy=silent_dcl_clear
Uses a less noisy way to clear the disk change line (which
doesn't involve seeks). Implied by daring.
floppy=<nr>,irq
Sets the floppy IRQ to <nr> instead of 6
floppy=<nr>,dma
Sets the floppy DMA channel to <nr> instead of 2
Supporting utilities and additional documentation:
==================================================
Additional parameters of the floppy driver can be configured at run
time. Utilities which do this can be found in the fdutils
package. This package also contains a new version of mtools which
allows to access high capacity disks (up to 1992K on a high density 3
1/2 disk!). It also contains additional documentation about the floppy
driver. It can be found at:
linux.wauug.org:/pub/knaff/fdutils/fdutils-4.3.src.tar.gz
sunsite.unc.edu:/pub/Linux/system/Misc/fdutils-4.3.src.tar.gz
tsx-11.mit.edu:/pub/linux/sources/sbin/fdutils-4.3.src.tar.gz
Alpha patches to these utilities are at:
http://www.club.innet.lu/~year3160/fdutils/ALPHA
All patches contained in this directory are directly against the base
version, i.e. DON'T APPLY THEM ON TOP OF EACH OTHER. Only apply the
most recent one.
Reporting problems about the floppy driver
==========================================
If you have a question or a bug report about the floppy driver, mail
me at Alain.Knaff@poboxes.com . If you post to Usenet, preferably use
comp.os.linux.hardware. As the volume in these groups is rather high,
be sure to include the word "floppy" (or "FLOPPY") in the subject
line. If the reported problem happens when mounting floppy disks, be
sure to mention also the type of the filesystem in the subject line.
Be sure to read the FAQ before mailing/posting any bug reports!
Alain
|
